Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
i2c: designware: amdisp: Fix resume-probe race condition issue
Identified resume-probe race condition in kernel v7.0 with the commit 38fa29b01a6a (“i2c: designware: Combine the init functions”),but this issue existed from the beginning though not detected.
The amdisp i2c device requires ISP to be in power-on state for probe to succeed. To meet this requirement, this device is added to genpd to control ISP power using runtime PM. The pm_runtime_get_sync() called before i2c_dw_probe() triggers PM resume, which powers on ISP and also invokes the amdisp i2c runtime resume before the probe completes resulting in this race condition and a NULL dereferencing issue in v7.0
Fix this race condition by using the genpd APIs directly during probe:
- Call dev_pm_genpd_resume() to Power ON ISP before probe
- Call dev_pm_genpd_suspend() to Power OFF ISP after probe
- Set the device to suspended state with pm_runtime_set_suspended()
- Enable runtime PM only after the device is fully initialized
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , RHEL 7 ELS , TuxCare 9.6 ESU
- Affected packages:
- kernel @ 5.14.0 (+6 more)